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CRISPR

Stands for Clustered Regularly Interspaced Short Palindromic Repeats.

The hallmark of a bacterial defense system that forms the basis for CRISPR-Cas9 genome editing technology.

Refers to the various CRISPR-Cas9 and -CPF1 systems that can be programmed to target specific stretches of genetic code and to edit DNA at precise locations.

The CRISPR genetic locus provides bacteria with a defense mechanism to protect them from repeated phage infections.

CRISPR-Cas9 Uses RNA oligonucleotides to guide the Cas9 enzyme to the target DNA sequence, and anti-sense oligonucleotides, which are single-stranded and suppress messenger RNA levels or alter messenger RNA splicing.
 
The single guide RNA   CRISPR-Cas9 routes and tethers the complex to a specific DNA sequence, the Cas9 enzyme cuts the targeted DNA, producing double strand breaks.

A gene editing technology.

A bacterial defense system that could be programmed to edit the human genome.
The technique is readily and cheaply designed to target almost any genome sequence, and at multiple sites at the same time.

Allows for tumor identification and permits selection of therapeutic agents with a high likelihood of killing a particular tumor, while minimizing side effects.

Has the potential to correct an array of disease causing genetic alterations.

It identifies specific target nucleotide regions using a guide strand of RNA and it unwinds the DNA utilizing an enzyme helicase.

Once the DNA is unwound CAS9, a nuclease-cutting enzyme induces double strand break in the DNA at the target site.

The most commonly used CAS9 enzyme is from Streptococcus pyogenes.

The gRNA molecule can be tailored to optimize hybridization with a particular DNA target site and guide the CAS9-gRNA complex to the site of the desired break.

The guidance of CAs9-gRNA to its target site is governed by the Watson-Crick base pairing.

With these systems, one can permanently modify genes in living cells and organisms and, may make it possible to correct mutations at precise locations in the human genome in order to treat genetic causes of disease.

Serve as part of the bacterial immune system, defending against invading viruses, and consist of repeating sequences of genetic code, interrupted by spacer sequences, which are remnants of genetic code from past invaders.

The system serves as a genetic memory that helps the cell detect and destroy invaders when they return.

CRISPR spacer sequences are transcribed into short RNA sequences capable of guiding the system to matching sequences of DNA.

Cas9 is one of the enzymes produced by the CRISPR system,binds to the DNA and cuts it, shutting the targeted gene off.

Using modified versions of Cas9, can activate gene expression instead of cutting the DNA.

CRISPR-Cas9 can be used to target and modify in the three-billion-letter sequence of the human genome in an effort to treat genetic disease.

An efficient alternative to other existing genome editing tools.

The CRISPR-Cas9 system is capable of cutting DNA strands, and do not need to be paired with separate cleaving enzymes.

Are easily matched with guide RNA (gRNA) sequences designed to lead them to their DNA targets.

Tens of thousands of such gRNA sequences have already been created.

Can also be used to target multiple genes simultaneously, another advantage that sets it apart from other gene-editing tools.

The DNA-cutting enzyme Cas9 forms a complex with two small RNAs, both of which are required for the cutting activity.

The Cpf1 system requires only a single RNA.

The Cpf1 enzyme is smaller than the standard SpCas9, making it easier to deliver into cells and tissues.

Cpf1 cuts DNA in a different manner than Cas9.

The Cas9 complex cuts DNA, at both strands at the same place, leaving ends that often undergo mutations as they are rejoined.

With the Cpf1 complex the cuts in the two strands are offset, leaving short overhangs on the exposed ends.

Leaving short overhangs helps with precise insertion, allowing integration into a piece of DNA more efficiently and accurately.

Cpf1 cuts far away from the recognition site, meaning that even it can likely still be re-cut, allowing multiple opportunities for correct editing to occur.

The Cpf1 system provides flexibility in choosing target sites.

Like Cas9, the Cpf1 complex must first attach to a short sequence known as a PAM, and targets must be chosen that are adjacent to naturally occurring PAM sequences.

The Cpf1 complex recognizes different PAM sequences from those of Cas9.

CRISPR is a family of DNA sequences in bacteria.

The sequences contain snippets of DNA from viruses that have attacked the bacterium.

These snippets are used by the bacterium to detect and destroy DNA from similar viruses during subsequent attacks.

These sequences play a key role in a bacterial defense system, and form the basis of a technology known as CRISPR/Cas9 that effectively and specifically changes genes within organisms.

The CRISPR/Cas system is a prokaryotic immune system.

The CRISPR/Cas system confers resistance to foreign genetic elements providing a form of acquired immunity.

RNA harboring the spacer sequence helps CRISPR-associated proteins recognize and cut exogenous DNA.

Cas proteins can cut foreign RNA.

A simple version of the CRISPR/Cas system, CRISPR/Cas9, has been modified to edit genomes.

The delivery of the Cas9 nuclease complexed with a synthetic guide RNA (gRNA) into a cell, allows the cell’s genome to be cut at a desired location, so existing genes can be removed and/or new ones added.

MAGESTIC-multiplexed accurate genome editing with short, trackable, integrated cellular barcodes refines CRISPR making it less like a blUNT DNA cutting instrument, and more like an efficient search and replace function on DNA material.

CRISPR/Cas9 used to target specific DNA sequences and cancer cells and replace the sequences with cancer killing genes instead.

Involves ex vivo technique with the gene editing outside the body, and subsequently an injecting the edited machinery into patients.

CRISPR-Cas systems have two classes. Class 1 systems use a complex of multiple Cas proteins to degrade foreign nucleic acids, and Class 2 systems use a single large Cas protein for the same purpose.

A patient with inherited blindness called Leber congenital amaurosis was the first person to undergo gene editing with CRISPRand  associated protein 9(Cas9).

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